knitroff 0.1.0

• First release.
• knit_roff() knits an .Rms document, troff with the ms macros and R chunks between .SS and .SE, to plain troff; render_roff() also typesets it with GNU groff as PDF, PostScript or a draft for the terminal.
• Inline results with `r expr` and .SR name expr; chunk listings with R’s prompts, optionally highlighted in bold and italic; figures with .PDFPIC or .PSPIC; roff_table() for tbl tables.
• A vignette engine, knitroff::roff, for .Rms vignettes.
• Reference help pages for writing documents: ?ms, ?troff, ?eqn and ?tbl.
• RStudio addins to insert a chunk and to render the open document.
• groff_available() tells whether groff can typeset here: finding the program is not enough, since Debian’s groff-base has no ms macros.